RFR: 8273438: Enable parallelism in vmTestbase/metaspace/stressHierarchy tests

[Mikhailo Seledtsov]

On Tue, 7 Sep 2021 15:07:10 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> Current `vmTestbase/metaspace/stressHierarchy` tests (part of vmTestbase_vm_metaspace suite) contains about 15 tests, each running exclusively. There seem to be no reason to run them exclusively, though: they complete in reasonable time, are single-threaded, and consume the usual amount of memory. There is no evidence in JBS that they ever timed out without a reason, and their history unfortunately predates OpenJDK to see why they were not concurrent from day one.
> 
> We should consider enabling parallelism for `vmTestbase/metaspace/stressHierarchy` and get improved test performance. Currently it is blocked by `TEST.properties` with `exclusiveAccess.dirs` directives in them. 
> 
> Note there are other exclusive tests in `vmTestbase_vm_metaspace`, but those seem to be the hard stress tests: pushing GC to the limits, or doing many threads, etc.
> 
> Motivational test time improvements below.
> 
> Before:
> 
> 
> $ time CONF=linux-x86_64-server-fastdebug make run-test TEST=vmTestbase_vm_metaspace | ts -s
> ...
> 00:24:53 ==============================
> 00:24:53 Test summary
> 00:24:53 ==============================
> 00:24:53    TEST                                              TOTAL  PASS  FAIL ERROR   
> 00:24:53    jtreg:test/hotspot/jtreg:vmTestbase_vm_metaspace     25    25     0     0   
> 00:24:53 ==============================
> 00:24:53 TEST SUCCESS
> 00:24:53 
> 00:24:53 Finished building target 'run-test' in configuration 'linux-x86_64-server-fastdebug'
> 
> real	24m53.389s
> user	53m2.029s
> sys	1m1.849s
> 
> 
> After:
> 
> 
> $ time CONF=linux-x86_64-server-fastdebug make run-test TEST=vmTestbase_vm_metaspace | ts -s
> ...
> 00:04:04 ==============================
> 00:04:04 Test summary
> 00:04:04 ==============================
> 00:04:04    TEST                                              TOTAL  PASS  FAIL ERROR   
> 00:04:04    jtreg:test/hotspot/jtreg:vmTestbase_vm_metaspace     25    25     0     0   
> 00:04:04 ==============================
> 00:04:04 TEST SUCCESS
> 00:04:04 
> 00:04:04 Finished building target 'run-test' in configuration 'linux-x86_64-server-fastdebug'
> 
> real	4m4.574s
> user	56m10.582s
> sys	1m4.725s

Stability testing passed with the change. Change looks good to me.

-------------

Marked as reviewed by mseledtsov (Committer).

PR: https://git.openjdk.java.net/jdk/pull/5391